How is the overall score calculated?

It is a weighted composite of five signals: sentiment (28%), rating (26%), volume (20%), completeness (16%), and recency (10%). Each is measured from public review data and listing information, then combined into a single 0-100 score.

Why does sentiment matter more than the star rating?

A star average can hide a repeated problem. Two businesses can share the same rating while one has a cluster of similar complaints in its recent reviews. Reading what reviews actually say is the only way to spot that, which is why sentiment is weighted highest.

What does a low-confidence label mean?

It means a business has few recent reviews, so the score is built on thin data. We label these clearly rather than presenting them with the same confidence as suppliers with a longer, more recent review history.

Can a solar supplier pay to improve its score?

No. Scores come only from the rubric and data described on this page. Paid placement, where it exists on the site, is always labelled and does not affect scoring. Any list with editor-reviewed picks or order discloses that directly on the page.

How we score solar energy equipment suppliers in Perth

What this page covers

Perth Solar Industry Guide currently scores 195 solar energy equipment supplier businesses across the Perth Metropolitan area. This page explains, in plain terms, how that score is built, why we weight the signals the way we do, and where the method falls short. We would rather you know the limits than assume the number is more precise than it is.

The five signals, heaviest first

Every business gets a composite score out of 100, built from five measured signals. Here they are in order of how much they count:

Sentiment, 28%. A synthesis of what recent reviews actually say, weighing praise against complaints on things like installation quality, follow-up service, and whether the system performs as promised.
Rating, 26%. The business's aggregate Google star rating.
Volume, 20%. How many reviews a business has, log-scaled so that ten reviews don't get treated the same as three hundred, but a small supplier isn't unfairly buried either.
Recency, 10%. How recently customers have left reviews, because a supplier that was great in 2019 and has gone quiet since tells you less than one being reviewed this month.
Completeness, 16%. Whether the basics are actually listed: phone number, website, trading hours, and a physical address.

Why sentiment carries the most weight

Two solar suppliers can sit at the same 4.3-star average and be nothing alike. One might have a spread of minor niggles across dozens of reviews. The other might have the same complaint repeated over and over: panels installed but the inverter never commissioned properly, or a system that underperforms and nobody returns calls about it. The star average hides that difference completely. Reading what recent reviews actually describe is the only way to catch a pattern like that before you sign a contract for equipment that's meant to run on your roof for 20-plus years. That's why sentiment is weighted above the raw star rating itself, not instead of it.

Why the other signals matter

Rating still matters because it's the most direct, widely understood summary of customer experience, and it's the number most people check first. Volume matters because a 5.0 rating from three reviews is a coin flip, not a track record, whereas a solid rating held across a hundred-plus reviews is much harder to fake or fluke. Recency matters because installer teams change, supply lines change, and a company's service quality now is what will actually handle your warranty claim in three years. Completeness matters in a practical way: a supplier who lists a working phone number, current hours, and a real address is easier to hold accountable if something goes wrong with a panel or inverter down the line.

The honest limits

Businesses with few recent reviews produce a shakier score, and we label these as low-confidence rather than pretend otherwise. We do not republish reviews wholesale; we synthesise the themes in them and link out to Google so you can read the original source yourself and form your own view. This is a scoring method, not a guarantee of workmanship or a substitute for getting your own quotes.

Scores are earned, not sold

Every score on this site comes from the rubric above and the underlying data only. Nothing is manually adjusted after the fact. Where paid placement exists anywhere on this site, it is always clearly labelled and it never changes a business's score. If any list on this site has picks or ordering that were editor-reviewed rather than purely score-driven, that is disclosed on the page itself, including on our best residential solar suppliers list.

Who's behind this

Perth Solar Industry Guide is published by Scout Local Media, an independent Australian publisher that has run local guides and business directories since 2026. Scout Local Media builds practical directories and consumer resources aimed at making it easier to pick a trustworthy local business, while also giving good local operators a fairer way to be found online. Editorial oversight of these rankings sits with Clara Tan, Editorial Director. You can reach the publisher at hello@scoutlocalmedia.com.au, or visit scoutlocalmedia.com.au and the Perth Solar Industry Guide home page for more.

FAQ

How is the overall score calculated?: It is a weighted composite of five signals: sentiment (28%), rating (26%), volume (20%), completeness (16%), and recency (10%). Each is measured from public review data and listing information, then combined into a single 0-100 score.
Why does sentiment matter more than the star rating?: A star average can hide a repeated problem. Two businesses can share the same rating while one has a cluster of similar complaints in its recent reviews. Reading what reviews actually say is the only way to spot that, which is why sentiment is weighted highest.
What does a low-confidence label mean?: It means a business has few recent reviews, so the score is built on thin data. We label these clearly rather than presenting them with the same confidence as suppliers with a longer, more recent review history.
Can a solar supplier pay to improve its score?: No. Scores come only from the rubric and data described on this page. Paid placement, where it exists on the site, is always labelled and does not affect scoring. Any list with editor-reviewed picks or order discloses that directly on the page.